An initial report into thermal performance of hemp and lime wall sections in the wise building at CAT

Conference paper

Rhydwen, Ranyl, Tucker, Simon, Butler, Arthur and Wijeyesekera, D.Chitral 2011. An initial report into thermal performance of hemp and lime wall sections in the wise building at CAT. Advances in Computing and Technology. University of East London, London Jan 2011 Lond University of East London, School of Architecture Computing and Engineering.

Hemp and binder (e.g. Lime) is an insulating wall matrix formed around a timberframe. It has multiple environmental benefits including sequestering carbon dioxide from theatmosphere into a building‟s walls and is thus of interest in the current climate situation.However the thermal performance of the matrix when evaluated using the steady statethermal conductivity (i.e. rate of heat transfer) is not as effective for the same thickness asother insulations. The world however is dynamic and in the Haverhill Housing Projectmonitored by the Building Research Establishment (UK) two hemp and lime houses, despitehaving a worse steady state thermal performance on paper, significantly outperformedcomparative standard houses (BRE 2002, 2003).The reasons for this unexpected performance are not clarified although the heat storagecapacity and the moisture handling ability of the matrix are possibilit ies. Hemp and bindermatrix has been shown to have considerable moisture handling and heat storage capabilitiesbut how or whether these improve thermal performance is not clear. All the tests reported sofar have been on the same binder yet there are many potential binders and each will changethe properties of the matrix and each has a different environmental legacy.To further clarify the in-building performance and to compare a range of binders, 5 differentbinder test wall sections in the Welsh Institute of Sustainable Education building at theCentre of Alternative Technology are being extensively monitored for heat flux, temperatureand moisture movements. This paper is an initial report of this experiment.

Citation: Rhydwen, R., Tucker, S., Butler, A. and Wijesekera, C., (2011)"An initial report into thermal performance of hemp and lime wall sections in the wise building at CAT" Advances in Computing and Technology, University of East London, January 2011, 52-59.